I read that when it first came out in the late 70's; supposedly it was influenced by the tour of the King Tut exhibit. Another book in that same vein (which preceded Motel, and which delves somewhat deeper into the division of religion and science is Walter Miller's A Canticle for Leibowitz, also very well worth taking the time to read.
That one is already on my To Do reading list. I’m reading Anna Karennina and then when I get bored with that I am also reading Catcher in the Rye.